The division of lymphocytes into different populations and subpopulations is emerging as an important basis for the understanding and classification of immunologic diseases. To date, there have been no attempts to study the populations and subpopulations of lymphocytes in the peripheral blood and tissues of patients with suspected immunologic diseases of the external eye. The applicants propose to perform these invesitgations on patients with ocular cicatricial pemphigold, Mooren's ulcer, herpetic and staphylococcal keratitis, corneal graft rejections, scleritis and episcleritis: 1. Peripheral blood. The proportions and numbers of T and B lymphocytes will be determined by rosette formation with untreated sheep erythrocytes for T cells and rosette formation with erythrocytes sensitized with mouse complement for B cells. K cells and T cell subpopulations will be further determined by surface receptors for the Fc portion of IgG or IgM. Antiserum to T cells and antisera to membrane immunoglobulins of B cells will also be employed. Monocytes will be identified by the myeloperoxidase stain. 2. Tissue specimens. We will attempt to determine whether the mononuclear cells associated with or predominating in these conditions are B cells or a particular supbpoulation of T cells associated with suppressor, helper or killer functions. Fluorescein labeled IgG-F (ab')2 with antibody activity against human immunoglobulins will be used to determine membrane immunoglobulins on B cells. T cells will be determined by anti-T cell serum utilizing immunofluorescent techniques and the formation of rosettes in tissue when exposed to untreated sheep erythrocytes. The subpopulations of T cells will be further determined by surface receptors capable of binding the Fc portion of IgM or IgG. Monocytes will be identified by morphologic studies and by the myeloperoxidase stain. Correlations with histopathological and direct immunofluorescent studies of tissue-fixed immunoglobulins and complement will be made. 3. Alterations in the numbers and proportions of circulating lymphocytes will be correlated with the lymphocyte types in tissue sections. It may be possible to correlate alterations in circulatng lymphocytes with disease activity and to monitor the effects of different forms of treatment on the circulating lymphocytes.